Support structures, such as mattresses, may include several foam layers of varying thicknesses to provide a support and cushioning characteristic desired by users. For example, a soft layer of foam may be situated close to the user to provide soft cushioning. A higher density layer of foam may be situated further away from the user to provide support as the whole weight of the user is applied to the support structure. The layers of foam are conventionally homogeneous structures manufactured using an extrusion or molding technique.
Users regularly desire a more complex cushioning characteristic than is often provided by homogeneous foam layers. For example, different parts of the user's body have different weights, and thereby a support structure made up of homogeneous mattress layers is difficult and expensive to customize to provide more support for the different parts of the user's body. Consistent with customization, more support for a user's torso is desired than for a user's legs, which are typically not as heavy as the torso. Foam material providing support is typically more dense and expensive than the softer layers of foam needed to support lighter parts of the user's body, such as the legs. A conventional homogeneous-foam-layer supporting structure provides the more costly foam material substantially across the entire mattress, thus making the structure more expensive than required or needed.
Further, there are heat and humidity issues often associated with such conventional support structures. Unlike innerspring mattresses, cushion structures with foam layers often trap heat and humidity within the foam layers, which may cause discomfort for some users. The heat and humidity may cause odors that may be undesirable within the support structure when the air is allowed to remain stagnant.
What is needed is a foam cushioning structure that is customizable to provide support to the user where needed, yet is lightweight, and reduces heat and humidity, which can cause undesirable odors.